A wide coral reef largely surrounds Sri Lanka perfect for your diving adventure. coastline making it ideal for diving. An underwater journey into the aquamarine waters of the Indian Ocean rewards you with glimpses of a totally different world, full of astounding color and life. Home to a magical variety of tropical fish and coral reefs, the calm ocean waters also laid claim to some historic wrecks that offer unusual exploration opportunities. The more laid-back activity of snorkelling is a popular past-time in many southern coastal areas while Pigeon Island in Nilaveli on the east coast offers some of the best.